During early bootup we can't use alloc_page, so to allocate
leaf pages in the P2M we need to use extend_brk. For that
we are utilizing the early_alloc_p2m and early_alloc_p2m_middle
functions to do the job for us. This function follows the
same logic as set_phys_to_machine.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If we want to use granted pages for AIO, changing the mappings of a user
vma and the corresponding p2m is not enough, we also need to update the
kernel mappings accordingly.
Currently this is only needed for pages that are created for user usages
through /dev/xen/gntdev. As in, pages that have been in use by the
kernel and use the P2M will not need this special mapping.
However there are no guarantees that in the future the kernel won't
start accessing pages through the 1:1 even for internal usage.

In order to avoid the complexity of dealing with highmem, we allocated
the pages lowmem.
We issue a HYPERVISOR_grant_table_op right away in
m2p_add_override and we remove the mappings using another
HYPERVISOR_grant_table_op in m2p_remove_override.
Considering that m2p_add_override and m2p_remove_override are called
once per page we use multicalls and hypercall batching.

Use the kmap_op pointer directly as argument to do the mapping as it is
guaranteed to be present up until the unmapping is done.
Before issuing any unmapping multicalls, we need to make sure that the
mapping has already being done, because we need the kmap->handle to be
set correctly.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
[v1: Removed GRANT_FRAME_BIT usage]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We dropped a lot of the MMU debugfs in favour of using
tracing API - but there is one which just provides
mostly static information that was made invisible by this change.

Bring it back.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The order-based approach is not only less efficient (requiring a shift
and a compare, typical generated code looking like this

	mov	eax, [machine_to_phys_order]
	mov	ecx, eax
	shr	ebx, cl
	test	ebx, ebx
	jnz	...

whereas a direct check requires just a compare, like in

	cmp	ebx, [machine_to_phys_nr]
	jae	...

), but also slightly dangerous in the 32-on-64 case - the element
address calculation can wrap if the next power of two boundary is
sufficiently far away from the actual upper limit of the table, and
hence can result in user space addresses being accessed (with it being
unknown what may actually be mapped there).

Additionally, the elimination of the mistaken use of fls() here (should
have been __fls()) fixes a latent issue on x86-64 that would trigger
if the code was run on a system with memory extending beyond the 44-bit
boundary.

CC: stable@kernel.org
Signed-off-by: NJan Beulich <jbeulich@novell.com>
[v1: Based on Jeremy's feedback]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We only supported the M2P (and P2M) override only for the
GNTMAP_contains_pte type mappings. Meaning that we grants
operations would "contain the machine address of the PTE to update"
If the flag is unset, then the grant operation is
"contains a host virtual address". The latter case means that
the Hypervisor takes care of updating our page table
(specifically the PTE entry) with the guest's MFN. As such we should
not try to do anything with the PTE. Previous to this patch
we would try to clear the PTE which resulted in Xen hypervisor
being upset with us:

(XEN) mm.c:1066:d0 Attempt to implicitly unmap a granted PTE c0100000ccc59067
(XEN) domain_crash called from mm.c:1067
(XEN) Domain 0 (vcpu#0) crashed on cpu#3:
(XEN) ----[ Xen-4.0-110228  x86_64  debug=y  Not tainted ]----

and crashing us.

This patch allows us to inhibit the PTE clearing in the PV guest
if the GNTMAP_contains_pte is not set.

On the m2p_remove_override path we provide the same parameter.

Sadly in the grant-table driver we do not have a mechanism to
tell m2p_remove_override whether to clear the PTE or not. Since
the grant-table driver is used by user-space, we can safely assume
that it operates only on PTE's. Hence the implementation for
it to work on !GNTMAP_contains_pte returns -EOPNOTSUPP. In the future
we can implement the support for this. It will require some extra
accounting structure to keep track of the page[i], and the flag.

[v1: Added documentation details, made it return -EOPNOTSUPP instead
 of trying to do a half-way implementation]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We only supported the M2P (and P2M) override only for the
GNTMAP_contains_pte type mappings. Meaning that we grants
operations would "contain the machine address of the PTE to update"
If the flag is unset, then the grant operation is
"contains a host virtual address". The latter case means that
the Hypervisor takes care of updating our page table
(specifically the PTE entry) with the guest's MFN. As such we should
not try to do anything with the PTE. Previous to this patch
we would try to clear the PTE which resulted in Xen hypervisor
being upset with us:

(XEN) mm.c:1066:d0 Attempt to implicitly unmap a granted PTE c0100000ccc59067
(XEN) domain_crash called from mm.c:1067
(XEN) Domain 0 (vcpu#0) crashed on cpu#3:
(XEN) ----[ Xen-4.0-110228  x86_64  debug=y  Not tainted ]----

and crashing us.

This patch allows us to inhibit the PTE clearing in the PV guest
if the GNTMAP_contains_pte is not set.

On the m2p_remove_override path we provide the same parameter.

Sadly in the grant-table driver we do not have a mechanism to
tell m2p_remove_override whether to clear the PTE or not. Since
the grant-table driver is used by user-space, we can safely assume
that it operates only on PTE's. Hence the implementation for
it to work on !GNTMAP_contains_pte returns -EOPNOTSUPP. In the future
we can implement the support for this. It will require some extra
accounting structure to keep track of the page[i], and the flag.

[v1: Added documentation details, made it return -EOPNOTSUPP instead
 of trying to do a half-way implementation]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If there is no proper PFN value in the M2P for the MFN
(so we get 0xFFFFF.. or 0x55555, or 0x0), we should
consult the M2P override to see if there is an entry for this.
[Note: we also consult the M2P override if the MFN
is past our machine_to_phys size].

We consult the P2M with the PFN. In case the returned
MFN is one of the special values: 0xFFF.., 0x5555
(which signify that the MFN can be either "missing" or it
belongs to DOMID_IO) or the p2m(m2p(mfn)) != mfn, we check
the M2P override. If we fail the M2P override check, we reset
the PFN value to INVALID_P2M_ENTRY.

Next we try to find the MFN in the P2M using the MFN
value (not the PFN value) and if found, we know
that this MFN is an identity value and return it as so.

Otherwise we have exhausted all the posibilities and we
return the PFN, which at this stage can either be a real
PFN value found in the machine_to_phys.. array, or
INVALID_P2M_ENTRY value.

[v1: Added Review-by tag]
Reviewed-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

.. beyound what we think is the end of memory. However there might
be more System RAM - but assigned to a guest. Hence jump to the
M2P override check and consult.

[v1: Added Review-by tag]
Reviewed-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We walk over the whole P2M tree and construct a simplified view of
which PFN regions belong to what level and what type they are.

Only enabled if CONFIG_XEN_DEBUG_FS is set.

[v2: UNKN->UNKNOWN, use uninitialized_var]
[v3: Rebased on top of mmu->p2m code split]
[v4: Fixed the else if]
Reviewed-by: NIan Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Our P2M tree structure is a three-level. On the leaf nodes
we set the Machine Frame Number (MFN) of the PFN. What this means
is that when one does: pfn_to_mfn(pfn), which is used when creating
PTE entries, you get the real MFN of the hardware. When Xen sets
up a guest it initially populates a array which has descending
(or ascending) MFN values, as so:

 idx: 0,  1,       2
 [0x290F, 0x290E, 0x290D, ..]

so pfn_to_mfn(2)==0x290D. If you start, restart many guests that list
starts looking quite random.

We graft this structure on our P2M tree structure and stick in
those MFN in the leafs. But for all other leaf entries, or for the top
root, or middle one, for which there is a void entry, we assume it is
"missing". So
 pfn_to_mfn(0xc0000)=INVALID_P2M_ENTRY.

We add the possibility of setting 1-1 mappings on certain regions, so
that:
 pfn_to_mfn(0xc0000)=0xc0000

The benefit of this is, that we can assume for non-RAM regions (think
PCI BARs, or ACPI spaces), we can create mappings easily b/c we
get the PFN value to match the MFN.

For this to work efficiently we introduce one new page p2m_identity and
allocate (via reserved_brk) any other pages we need to cover the sides
(1GB or 4MB boundary violations). All entries in p2m_identity are set to
INVALID_P2M_ENTRY type (Xen toolstack only recognizes that and MFNs,
no other fancy value).

On lookup we spot that the entry points to p2m_identity and return the identity
value instead of dereferencing and returning INVALID_P2M_ENTRY. If the entry
points to an allocated page, we just proceed as before and return the PFN.
If the PFN has IDENTITY_FRAME_BIT set we unmask that in appropriate functions
(pfn_to_mfn).

The reason for having the IDENTITY_FRAME_BIT instead of just returning the
PFN is that we could find ourselves where pfn_to_mfn(pfn)==pfn for a
non-identity pfn. To protect ourselves against we elect to set (and get) the
IDENTITY_FRAME_BIT on all identity mapped PFNs.

This simplistic diagram is used to explain the more subtle piece of code.
There is also a digram of the P2M at the end that can help.
Imagine your E820 looking as so:

                   1GB                                           2GB
/-------------------+---------\/----\         /----------\    /---+-----\
| System RAM        | Sys RAM ||ACPI|         | reserved |    | Sys RAM |
\-------------------+---------/\----/         \----------/    \---+-----/
                              ^- 1029MB                       ^- 2001MB

[1029MB = 263424 (0x40500), 2001MB = 512256 (0x7D100), 2048MB = 524288 (0x80000)]

And dom0_mem=max:3GB,1GB is passed in to the guest, meaning memory past 1GB
is actually not present (would have to kick the balloon driver to put it in).

When we are told to set the PFNs for identity mapping (see patch: "xen/setup:
Set identity mapping for non-RAM E820 and E820 gaps.") we pass in the start
of the PFN and the end PFN (263424 and 512256 respectively). The first step is
to reserve_brk a top leaf page if the p2m[1] is missing. The top leaf page
covers 512^2 of page estate (1GB) and in case the start or end PFN is not
aligned on 512^2*PAGE_SIZE (1GB) we loop on aligned 1GB PFNs from start pfn to
end pfn.  We reserve_brk top leaf pages if they are missing (means they point
to p2m_mid_missing).

With the E820 example above, 263424 is not 1GB aligned so we allocate a
reserve_brk page which will cover the PFNs estate from 0x40000 to 0x80000.
Each entry in the allocate page is "missing" (points to p2m_missing).

Next stage is to determine if we need to do a more granular boundary check
on the 4MB (or 2MB depending on architecture) off the start and end pfn's.
We check if the start pfn and end pfn violate that boundary check, and if
so reserve_brk a middle (p2m[x][y]) leaf page. This way we have a much finer
granularity of setting which PFNs are missing and which ones are identity.
In our example 263424 and 512256 both fail the check so we reserve_brk two
pages. Populate them with INVALID_P2M_ENTRY (so they both have "missing" values)
and assign them to p2m[1][2] and p2m[1][488] respectively.

At this point we would at minimum reserve_brk one page, but could be up to
three. Each call to set_phys_range_identity has at maximum a three page
cost. If we were to query the P2M at this stage, all those entries from
start PFN through end PFN (so 1029MB -> 2001MB) would return INVALID_P2M_ENTRY
("missing").

The next step is to walk from the start pfn to the end pfn setting
the IDENTITY_FRAME_BIT on each PFN. This is done in 'set_phys_range_identity'.
If we find that the middle leaf is pointing to p2m_missing we can swap it over
to p2m_identity - this way covering 4MB (or 2MB) PFN space.  At this point we
do not need to worry about boundary aligment (so no need to reserve_brk a middle
page, figure out which PFNs are "missing" and which ones are identity), as that
has been done earlier.  If we find that the middle leaf is not occupied by
p2m_identity or p2m_missing, we dereference that page (which covers
512 PFNs) and set the appropriate PFN with IDENTITY_FRAME_BIT. In our example
263424 and 512256 end up there, and we set from p2m[1][2][256->511] and
p2m[1][488][0->256] with IDENTITY_FRAME_BIT set.

All other regions that are void (or not filled) either point to p2m_missing
(considered missing) or have the default value of INVALID_P2M_ENTRY (also
considered missing). In our case, p2m[1][2][0->255] and p2m[1][488][257->511]
contain the INVALID_P2M_ENTRY value and are considered "missing."

This is what the p2m ends up looking (for the E820 above) with this
fabulous drawing:

   p2m         /--------------\
 /-----\       | &mfn_list[0],|                           /-----------------\
 |  0  |------>| &mfn_list[1],|    /---------------\      | ~0, ~0, ..      |
 |-----|       |  ..., ~0, ~0 |    | ~0, ~0, [x]---+----->| IDENTITY [@256] |
 |  1  |---\   \--------------/    | [p2m_identity]+\     | IDENTITY [@257] |
 |-----|    \                      | [p2m_identity]+\\    | ....            |
 |  2  |--\  \-------------------->|  ...          | \\   \----------------/
 |-----|   \                       \---------------/  \\
 |  3  |\   \                                          \\  p2m_identity
 |-----| \   \-------------------->/---------------\   /-----------------\
 | ..  +->+                        | [p2m_identity]+-->| ~0, ~0, ~0, ... |
 \-----/ /                         | [p2m_identity]+-->| ..., ~0         |
        / /---------------\        | ....          |   \-----------------/
       /  | IDENTITY[@0]  |      /-+-[x], ~0, ~0.. |
      /   | IDENTITY[@256]|<----/  \---------------/
     /    | ~0, ~0, ....  |
    |     \---------------/
    |
    p2m_missing             p2m_missing
/------------------\     /------------\
| [p2m_mid_missing]+---->| ~0, ~0, ~0 |
| [p2m_mid_missing]+---->| ..., ~0    |
\------------------/     \------------/

where ~0 is INVALID_P2M_ENTRY. IDENTITY is (PFN | IDENTITY_BIT)
Reviewed-by: NIan Campbell <ian.campbell@citrix.com>
[v5: Changed code to use ranges, added ASCII art]
[v6: Rebased on top of xen->p2m code split]
[v4: Squished patches in just this one]
[v7: Added RESERVE_BRK for potentially allocated pages]
[v8: Fixed alignment problem]
[v9: Changed 1<<3X to 1<<BITS_PER_LONG-X]
[v10: Copied git commit description in the p2m code + Add Review tag]
[v11: Title had '2-1' - should be '1-1' mapping]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

With this patch, we diligently set regions that will be used by the
balloon driver to be INVALID_P2M_ENTRY and under the ownership
of the balloon driver. We are OK using the __set_phys_to_machine
as we do not expect to be allocating any P2M middle or entries pages.
The set_phys_to_machine has the side-effect of potentially allocating
new pages and we do not want that at this stage.

We can do this because xen_build_mfn_list_list will have already
allocated all such pages up to xen_max_p2m_pfn.

We also move the check for auto translated physmap down the
stack so it is present in __set_phys_to_machine.

[v2: Rebased with mmu->p2m code split]
Reviewed-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When adding a page to m2p_override we change the p2m of the page so we
need to also clear the old pte of the kernel linear mapping because it
doesn't correspond anymore.

When we remove the page from m2p_override we restore the original p2m of
the page and we also restore the old pte of the kernel linear mapping.

Before changing the p2m mappings in m2p_add_override and
m2p_remove_override, check that the page passed as argument is valid and
return an error if it is not.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Add a simple hashtable based mechanism to override some portions of the
m2p, so that we can find out the pfn corresponding to an mfn of a
granted page. In fact entries corresponding to granted pages in the m2p
hold the original pfn value of the page in the source domain that
granted it.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This hypercall allows Xen to specify a non-default location for the
machine to physical mapping. This capability is used when running a 32
bit domain 0 on a 64 bit hypervisor to shrink the hypervisor hole to
exactly the size required.

[ Impact: add Xen hypercall definitions ]
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

When setting up a pte for a missing pfn (no matching mfn), just create
an empty pte rather than a junk mapping.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

set_phys_to_machine() can return false on failure, which means a memory
allocation failure for the p2m structure.  It can only fail if setting
the mfn for a pfn in previously unused address space.  It is guaranteed
to succeed if you're setting a mapping to INVALID_P2M_ENTRY or updating
the mfn for an existing pfn.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

Add xen_set_domain_pte() to allow setting a pte mapping a page from
another domain.  The common case is to map from DOMID_IO, the pseudo
domain which owns all IO pages, but will also be used in the privcmd
interface to map other domain pages.

[ Impact: new Xen-internal API for cross-domain mappings ]
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

In a Xen domain, ioremap operates on machine addresses, not
pseudo-physical addresses.  We use _PAGE_IOMAP to determine whether a
mapping is intended for machine addresses.

[ Impact: allow Xen domain to map real hardware ]
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Signed-off-by: NAlex Nixon <alex.nixon@citrix.com>

Signed-off-by: NAlex Nixon <alex.nixon@citrix.com>

The virtually mapped percpu space causes us two problems:

 - for hypercalls which take an mfn, we need to do a full pagetable
   walk to convert the percpu va into an mfn, and

 - when a hypercall requires a page to be mapped RO via all its aliases,
   we need to make sure its RO in both the percpu mapping and in the
   linear mapping

This primarily affects the gdt and the vcpu info structure.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

On an x86 system which doesn't support global mappings,
__supported_pte_mask has _PAGE_GLOBAL clear, to make sure it never
appears in the PTE.  pfn_pte() and so on will enforce it with:

static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
{
	return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
		      pgprot_val(pgprot)) & __supported_pte_mask);
}

However, we overload _PAGE_GLOBAL with _PAGE_PROTNONE on non-present
ptes to distinguish them from swap entries.  However, applying
__supported_pte_mask indiscriminately will clear the bit and corrupt the
pte.

I guess the best fix is to only apply __supported_pte_mask to present
ptes.  This seems like the right solution to me, as it means we can
completely ignore the issue of overlaps between the present pte bits and
the non-present pte-as-swap entry use of the bits.

__supported_pte_mask contains the set of flags we support on the
current hardware.  We also use bits in the pte for things like
logically present ptes with no permissions, and swap entries for
swapped out pages.  We should only apply __supported_pte_mask to
present ptes, because otherwise we may destroy other information being
stored in the ptes.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: cleanup

hypervisor.h had accumulated a lot of crud, including lots of spurious
#includes.  Clean it all up, and go around fixing up everything else
accordingly.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Drop double underscores from header guards in arch/x86/include.  They
are used inconsistently, and are not necessary.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

PFN_PHYS, as its name suggests, turns a pfn into a physical address.
However, it is a macro which just operates on its argument without
modifying its type.  pfns are typed unsigned long, but an unsigned
long may not be long enough to hold a physical address (32-bit systems
with more than 32 bits of physcial address).

Make sure we cast to phys_addr_t to return a complete result.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch is the result of an automatic script that consolidates the
format of all the headers in include/asm-x86/.

The format:

1. No leading underscore. Names with leading underscores are reserved.
2. Pathname components are separated by two underscores. So we can
   distinguish between mm_types.h and mm/types.h.
3. Everything except letters and numbers are turned into single
   underscores.
Signed-off-by: NVegard Nossum <vegard.nossum@gmail.com>

Rusty, in his peevish way, complained that macros defining constants
should have a name which somewhat accurately reflects the actual
purpose of the constant.

Aside from the fact that PTE_MASK gives no clue as to what's actually
being masked, and is misleadingly similar to the functionally entirely
different PMD_MASK, PUD_MASK and PGD_MASK, I don't really see what the
problem is.

But if this patch silences the incessent noise, then it will have
achieved its goal (TODO: write test-case).
Signed-off-by: NJeremy Fitzhardinge <jeremy@goop.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When building initial pagetables in 64-bit kernel the pud/pmd pointer may
be in ioremap/fixmap space, so we need to walk the pagetable to look up the
physical address.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need extra pv_mmu_ops for 64-bit, to deal with the extra level of
pagetable.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add a config option to set the max size of a Xen domain.  This is used
to scale the size of the physical-to-machine array; it ends up using
around 1 page/GByte, so there's no reason to be very restrictive.

For a 32-bit guest, the default value of 8GB is probably sufficient;
there's not much point in giving a 32-bit machine much more memory
than that.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

We now support the use of memory hotplug, so the physical to machine
page mapping structure must be dynamic.  This is implemented as a
two-level radix tree structure, which allows us to efficiently
incrementally allocate memory for the p2m table as new pages are
added.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use PTE_MASK to extract mfn from pte.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Tested-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The definitions in include/asm/xen/page.h are arch specific.
ia64/xen wants to define its own version. So move them to arch specific
directory and keep include/xen/page.h in order not to break compilation.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Xen's pte operations on mfns can be unified like the kernel's pfn operations.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make sure pte_t, whatever its definition, has a pte element with type
pteval_t.  This allows common code to access it without needing to be
specifically parameterised on what pagetable mode we're compiling for.
For 32-bit, this means that pte_t becomes a union with "pte" and "{
pte_low, pte_high }" (PAE) or just "pte_low" (non-PAE).
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>